/**
* SECTION:gstbus
+ * @title: GstBus
* @short_description: Asynchronous message bus subsystem
* @see_also: #GstMessage, #GstElement
*
#include "gstbus.h"
#include "glib-compat-private.h"
+#ifdef G_OS_WIN32
+# ifndef EWOULDBLOCK
+# define EWOULDBLOCK EAGAIN /* This is just to placate gcc */
+# endif
+#endif /* G_OS_WIN32 */
+
#define GST_CAT_DEFAULT GST_CAT_BUS
/* bus signals */
enum
};
#define gst_bus_parent_class parent_class
-G_DEFINE_TYPE (GstBus, gst_bus, GST_TYPE_OBJECT);
+G_DEFINE_TYPE_WITH_PRIVATE (GstBus, gst_bus, GST_TYPE_OBJECT);
static void
gst_bus_set_property (GObject * object,
bus->priv->poll = gst_poll_new_timer ();
gst_poll_get_read_gpollfd (bus->priv->poll, &bus->priv->pollfd);
}
+
+ G_OBJECT_CLASS (gst_bus_parent_class)->constructed (object);
}
static void
G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
G_STRUCT_OFFSET (GstBusClass, message), NULL, NULL,
g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_MESSAGE);
-
- g_type_class_add_private (klass, sizeof (GstBusPrivate));
}
static void
gst_bus_init (GstBus * bus)
{
- bus->priv = G_TYPE_INSTANCE_GET_PRIVATE (bus, GST_TYPE_BUS, GstBusPrivate);
+ bus->priv = gst_bus_get_instance_private (bus);
bus->priv->enable_async = DEFAULT_ENABLE_ASYNC;
g_mutex_init (&bus->priv->queue_lock);
bus->priv->queue = gst_atomic_queue_new (32);
- /* clear floating flag */
- gst_object_ref_sink (bus);
-
GST_DEBUG_OBJECT (bus, "created");
}
{
GstBus *result;
- result = g_object_newv (gst_bus_get_type (), 0, NULL);
+ result = g_object_new (gst_bus_get_type (), NULL);
GST_DEBUG_OBJECT (result, "created new bus");
+ /* clear floating flag */
+ gst_object_ref_sink (result);
+
return result;
}
GST_DEBUG_OBJECT (bus, "[msg %p] posting on bus %" GST_PTR_FORMAT, message,
message);
+ /* check we didn't accidentally add a public flag that maps to same value */
+ g_assert (!GST_MINI_OBJECT_FLAG_IS_SET (message,
+ GST_MESSAGE_FLAG_ASYNC_DELIVERY));
+
GST_OBJECT_LOCK (bus);
/* check if the bus is flushing */
if (GST_OBJECT_FLAG_IS_SET (bus, GST_BUS_FLUSHING))
g_cond_init (cond);
g_mutex_init (lock);
+ GST_MINI_OBJECT_FLAG_SET (message, GST_MESSAGE_FLAG_ASYNC_DELIVERY);
+
GST_DEBUG_OBJECT (bus, "[msg %p] waiting for async delivery", message);
/* now we lock the message mutex, send the message to the async
/* now block till the message is freed */
g_cond_wait (cond, lock);
+
+ /* we acquired a new ref from gst_message_dispose() so we can clean up */
g_mutex_unlock (lock);
GST_DEBUG_OBJECT (bus, "[msg %p] delivered asynchronously", message);
+ GST_MINI_OBJECT_FLAG_UNSET (message, GST_MESSAGE_FLAG_ASYNC_DELIVERY);
+
g_mutex_clear (lock);
g_cond_clear (cond);
+
+ gst_message_unref (message);
break;
}
default:
is_flushing:
{
GST_DEBUG_OBJECT (bus, "bus is flushing");
- gst_message_unref (message);
GST_OBJECT_UNLOCK (bus);
+ gst_message_unref (message);
return FALSE;
}
gst_bus_set_flushing (GstBus * bus, gboolean flushing)
{
GstMessage *message;
+ GList *message_list = NULL;
+
+ g_return_if_fail (GST_IS_BUS (bus));
GST_OBJECT_LOCK (bus);
GST_DEBUG_OBJECT (bus, "set bus flushing");
while ((message = gst_bus_pop (bus)))
- gst_message_unref (message);
+ message_list = g_list_prepend (message_list, message);
} else {
GST_DEBUG_OBJECT (bus, "unset bus flushing");
GST_OBJECT_FLAG_UNSET (bus, GST_BUS_FLUSHING);
}
GST_OBJECT_UNLOCK (bus);
+
+ g_list_free_full (message_list, (GDestroyNotify) gst_message_unref);
}
/**
gst_atomic_queue_length (bus->priv->queue));
while ((message = gst_atomic_queue_pop (bus->priv->queue))) {
- if (bus->priv->poll)
- gst_poll_read_control (bus->priv->poll);
+ if (bus->priv->poll) {
+ while (!gst_poll_read_control (bus->priv->poll)) {
+ if (errno == EWOULDBLOCK) {
+ /* Retry, this can happen if pushing to the queue has finished,
+ * popping here succeeded but writing control did not finish
+ * before we got to this line. */
+ /* Give other threads the chance to do something */
+ g_thread_yield ();
+ continue;
+ } else {
+ /* This is a real error and means that either the bus is in an
+ * inconsistent state, or the GstPoll is invalid. GstPoll already
+ * prints a critical warning about this, no need to do that again
+ * ourselves */
+ break;
+ }
+ }
+ }
GST_DEBUG_OBJECT (bus, "got message %p, %s from %s, type mask is %u",
message, GST_MESSAGE_TYPE_NAME (message),
if ((GST_MESSAGE_TYPE (message) & types) != 0) {
/* Extra check to ensure extended types don't get matched unless
* asked for */
- if ((GST_MESSAGE_TYPE_IS_EXTENDED (message) == FALSE)
+ if ((!GST_MESSAGE_TYPE_IS_EXTENDED (message))
|| (types & GST_MESSAGE_EXTENDED)) {
/* exit the loop, we have a message */
goto beach;
}
}
+/**
+ * gst_bus_get_pollfd:
+ * @bus: A #GstBus
+ * @fd: (out): A GPollFD to fill
+ *
+ * Gets the file descriptor from the bus which can be used to get notified about
+ * messages being available with functions like g_poll(), and allows integration
+ * into other event loops based on file descriptors.
+ * Whenever a message is available, the POLLIN / %G_IO_IN event is set.
+ *
+ * Warning: NEVER read or write anything to the returned fd but only use it
+ * for getting notifications via g_poll() or similar and then use the normal
+ * GstBus API, e.g. gst_bus_pop().
+ *
+ * Since: 1.14
+ */
+void
+gst_bus_get_pollfd (GstBus * bus, GPollFD * fd)
+{
+ g_return_if_fail (GST_IS_BUS (bus));
+ g_return_if_fail (bus->priv->poll != NULL);
+
+ *fd = bus->priv->pollfd;
+}
+
/* GSource for the bus
*/
typedef struct
* a message is on the bus. After the GSource is dispatched, the
* message is popped off the bus and unreffed.
*
- * Returns: (transfer full): a #GSource that can be added to a mainloop.
+ * Returns: (transfer full) (nullable): a #GSource that can be added to a mainloop.
*/
GSource *
gst_bus_create_watch (GstBus * bus)
}
source = gst_bus_create_watch (bus);
+ if (!source) {
+ g_critical ("Creating bus watch failed");
+ return 0;
+ }
if (priority != G_PRIORITY_DEFAULT)
g_source_set_priority (source, priority);
* There can only be a single bus watch per bus, you must remove it before you
* can set a new one.
*
+ * The bus watch will only work if a GLib main loop is being run.
+ *
* When @func is called, the message belongs to the caller; if you want to
* keep a copy of it, call gst_message_ref() before leaving @func.
*
* from @func. If the watch was added to the default main context it is also
* possible to remove the watch using g_source_remove().
*
+ * The bus watch will take its own reference to the @bus, so it is safe to unref
+ * @bus using gst_object_unref() after setting the bus watch.
+ *
* MT safe.
*
* Returns: The event source id or 0 if @bus already got an event source.
* There can only be a single bus watch per bus, you must remove it before you
* can set a new one.
*
+ * The bus watch will only work if a GLib main loop is being run.
+ *
* The watch can be removed using gst_bus_remove_watch() or by returning %FALSE
* from @func. If the watch was added to the default main context it is also
* possible to remove the watch using g_source_remove().
*
- * Returns: The event source id or 0 if @bus already got an event source.
+ * The bus watch will take its own reference to the @bus, so it is safe to unref
+ * @bus using gst_object_unref() after setting the bus watch.
*
* MT safe.
+ *
+ * Returns: The event source id or 0 if @bus already got an event source.
*/
guint
gst_bus_add_watch (GstBus * bus, GstBusFunc func, gpointer user_data)
GstMessage *ret;
gulong id;
+ g_return_val_if_fail (GST_IS_BUS (bus), NULL);
+
poll_data = g_slice_new (GstBusPollData);
poll_data->source_running = TRUE;
poll_data->loop = g_main_loop_new (NULL, FALSE);